For the mass-market adoption of environmentally benign electric vehicles a breakthrough in battery technology in terms of specific energy and cost is needed. Specific energy, also known as energy density, is the stored heat or other thermodynamic property of a substance, which for these purposes should be its useful or extractable energy. Among the candidate chemistries being considered, non-aqueous Li-air batteries are attractive due to their high specific energy and relatively low cost. However, the limited discharge capacity and rechargeability are two key issues that limit their practicality. The proposed research of using electrolyte additives could increase the limited discharge capacity of current non-aqueous Li-air batteries without sacrificing battery rechargeability. The methods and findings will also be broadly applicable to other metal-air battery technologies currently being pursued, such as sodium-air, magnesium-air and potassium-air.
Robust electrode/electrolyte interfaces are a crucial requirement for the long-term reliability of fuel cells and batteries. This proposal addresses the mesoscale electrode/electrolyte problem in the context of electrochemical systems using two model problems: (i) tune the electrode/electrolyte interface through electrolyte modification to tailor the activity and selectivity of Pt group metals for aqueous oxygen reduction reaction and (ii) design compatible electrode and electrolyte combinations that possess interfacial stability in lithium-air batteries while solubilizing the discharge product.
If successful, these batteries could advance the adoption of electric vehicles for reduced emissions, greater efficiency, and increased domestic energy security. The PI ran a successful massive open online course (MOOC) from Carnegie Mellon University on Statistical Thermodynamics and intends to continue offering this annually. He will supplement the MOOC by developing learning kits, which can be remotely 3D printed. He will also develop a new course on electrochemical energy systems and develop the course notes into an interactive and animation-rich in-progress electronic-textbook and will conduct workshops on "How batteries work?" at underrepresented Pittsburgh public schools with the aim of illustrating basic principles of thermodynamics.
